Re-introduced the missing Triangle check in TIN

src/PolyhedralSurface.php

@@ -191,14 +191,4 @@ public function getIterator()
     {
         return new \ArrayIterator($this->patches);
     }
-
-    /**
-     * Returns the FQCN of the contained Geometry type.
-     *
-     * @return string
-     */
-    protected static function containedGeometryType()
-    {
-        return Polygon::class;
-    }
 }

src/TIN.php

@@ -2,26 +2,36 @@
 
 namespace Brick\Geo;
 
+use Brick\Geo\Exception\UnexpectedGeometryException;
+
 /**
  * A TIN (triangulated irregular network) is a PolyhedralSurface consisting only of Triangle patches.
  */
 class TIN extends PolyhedralSurface
 {
     /**
-     * @noproxy
-     *
      * {@inheritdoc}
+     *
+     * @throws UnexpectedGeometryException If the patches are not triangles.
      */
-    public function geometryType()
+    public function __construct(CoordinateSystem $cs, Polygon ...$patches)
     {
-        return 'TIN';
+        parent::__construct($cs, ...$patches);
+
+        foreach ($patches as $patch) {
+            if (! $patch instanceof Triangle) {
+                throw new UnexpectedGeometryException('The patches in a TIN must be triangles.');
+            }
+        }
     }
 
     /**
+     * @noproxy
+     *
      * {@inheritdoc}
      */
-    protected static function containedGeometryType()
+    public function geometryType()
     {
-        return Triangle::class;
+        return 'TIN';
     }
 }